1. doc.: IEEE 802.11-13/484r0 Submission NameAffiliationsAddressPhoneemail George Cherian Santosh Abraham Qualcomm 5775 Morehouse Dr, San Diego, CA, USA +1 (858)-651-6645 +1 (858)-651-6107 gcherian@qti.qualcomm.com sabraham@qti.qualcomm.com Jouni MalinenQualcomm Hermiankatu 6-8 D Tampere, Finland jouni@qca.qualcomm.com Power save during Fast Initial Link Setup Date: 2015-05-13 May 2013 Slide 1 Authors: Qualcomm

2. doc.: IEEE 802.11-13/484r0 Submission May 2013 Slide 2 Abstract This document proposes a solution for power save issue pointed out in 13/414 Qualcomm

3. doc.: IEEE 802.11-13/484r0 Submission Problem Description IEEE 802.11ai redesigned the authentication mechanism as shown below. In the 802.11ai design, a single roundtrip of Authentication signaling is performed prior to the Association So, the STA will not be able to sleep between steps 1 & 4

4. doc.: IEEE 802.11-13/484r0 Submission However… The time period between steps 1-4 is not expected to be very large –In most cases, it will be less than 100ms –But a poor backhaul to the authentication server can cause additional delay Do we want to optimize power during this time? –If Yes, two potential options are proposed in this contribution May 2013 QualcommSlide 4

5. doc.: IEEE 802.11-13/484r0 Submission Option-1: Enter Power-save mode based on Authentication frame Limitation FILS association may be delayed depending on how often the beacon frames are broadcasted Advantage AP doesn’t need an accurate estimate of the delay from AS No additional signaling messages STA requests the following at Step-1 “request for PS mode operation”, “maximum wait-time” AP operation upon receiving Step-1 If AP is sure to get response back from AS within “maximum wait-time”, then the AP behaves as is defined in the current draft (see also slide-3) Otherwise the AP sends an Association ID during authentication exchange (shown in Step 3) –“EAP-RP: Finish Reauth” is not included in the Authentication Response frame (message-3 in the above diagram) –The validity of the association ID is set to several TBTTs as chosen by the AP –STA derives the key after step3 STA enters power save mode upon receiving message-3. STA periodically wakes up to see if it gets paged –AP pages the STA when it receives the Authentication Response from the Authentication Server –STA responds to the page by sending Association Request AP includes the response from AS in the Association Response IP address assignment with large backhaul delay Proposed technique is helpful for IP address assignment also, when the backhaul delay for IP address assignment is large (which can be the case when DHCP is used for IP address assignment) The STA can operate in power-save mode after sending Association Request frame AP will page the device when the AP is ready with the Association Response May 2013

6. doc.: IEEE 802.11-13/484r0 Submission Option-2: STA to delay Association Request STA requests the following at Step-1 “request for PS mode operation”, “maximum wait-time” AP operation upon receiving Step-1 If AP is sure to get response back from AS within “maximum wait-time”, then the AP behaves as is defined in the current draft (see also slide-3) Otherwise the AP sends “Response Delay Estimate” at step-4 –“EAP-RP: Finish Reauth” is not included in step-4 STA holds Association Request based on the “Response delay estimate” AP includes the response from AS in the Association Response If the AP hasn’t received response from the AS yet, the AP holds the Association Response until a maximum time chosen by the AP Limitation “Response delay estimate” may not be accurate. Advantage FILS association is not delayed (if estimation is accurate) No additional signaling messages May 2013

7. doc.: IEEE 802.11-13/484r0 Submission Straw polls Do you support optimizing power during FILS Association? –Yes –No –Need More information Do you prefer : option-1 (STA to operate in power-save mode after receiving Auth Response) or option-2 (AP to include expected backhaul delay in Auth Response) –Option-1 –Option-2 –Either is okay –Neither May 2013 QualcommSlide 7